Valve for machines having a reciprocating piston



June 1964 N. E. B. LARSSON 79 VALVE FOR MACHINES HAVING A RECIPROCATINGPISTON Original Filed March 23, 1959 2 Sheets-Sheet l 14 75 7 Q '-l5 i27 8 27 JW/Z/ iVI'f/z/ June 1964 N. E. B. LARSSON VALVE FOR MACHINESHAVING A RECIPROCATING PISTON 2, Sheets-Sheet 2 FIG. 71).

Original Filed March 25, 1959 FIG. 7a.

United States Patent ,1 5, 79 VALVE FOR MACHINES HAVING A RECIPROCATINGPISTON N r k. 'et awso qdemi msxa .15

a i we en Original application Mar. 23, 1959;, Ser. No. 801,232.Dividedand "this application May 29,1961, Ser. N0 113,338

1 Claim. (Cl. 230-229) The present invention relates to machines hayinga reciprocating piston, such as for instance compressors, and moreparticularly to a valve mechanism, for such machines of a type includingan annular or polygonal valve seat having substantially radial openingsfor the passage of thework in g medium, and an. automatically operatingvalve body provided in front of said openings or surroundingthe valveseat for controlling the passage of a m m t rou h said op n gs- Afeature of the inyention involves that the valve body and the valve seatare i qtatablym ounted with relation to each other in order to permitunloading of the machine by uncovering said openings.

The subject matter of the present invention is disclosed in 'my pendingapplicationSerial No. 801,232, filed March 23,1959, fro m which thepresent application is divided out.

In the accompanying drawing FIG. 1 is an axial section of the piston andthe uppermost portion of a compressor having a valve mechanism accordingto the invention. FIGS. la and 1b are diametrically opposite portions ofan axial cross-sectional view of a valve mechanism according to theinvention used as intake valve for a compressor cylinder. FIGS. 2 and 3are elevations looking from inside of a portion of said valve mechanismwith the valve seat and the valve body shown in two different positionswith relation to each other. FIG. 4 is a top plan view of FIG. 1a withcertain portions shown in horizontal section. FIGS. 5 and 6 are top planviews of a detail portion of FIG. 4 with the valve body shown indifferent positions.

With reference to FIG. 1, the numeral 1 designates the cylinder wall ofa piston type of compressor, 2 is the up and down movable pistonthereof, and 3 is a pivot for hingedly connecting a piston rod, notshown, to the piston 2. Supported on the top edge of the cylinder wall 1is an annular member 4 forming an extension of the cylinder Wall 1. Saidmember 4 is constructed and arranged so as to act as the seat of a valvemechanism for admitting to the cylinder the medium to be compressedtherein by the action of the piston, said medium being hereinafterreferred to as the working medium.

Resting on the top edge of the seat member 4 is an annular member 5forming the top portion of the cylinder wall. Said annular member 5 isfitted in a boring in the compressor frame designated as a whole by 6and is tightened therein by means of a sealing ring 7. Resting on thetop edge of the wall member 5 is a yoke 8 which supports by means of acentral bolt 9 and its head 10 a cylinder cover 11 having, in theembodiment shown, a curved lower surface and a plane upper surface.

Clamped between the cylinder cover and the yoke is a flat disc 12 havinga downwardly extended hub portion 13 surrounding the bolt. Said extendedhub portion bears upon the cover 11 so as thereby to maintain the disc12 at a distance above the plane upper surface of the cylinder cover.

The cylinder cover 11, the disc 12 and the yoke 8 are all clampedtogether in the longitudinal direction of the bolt by means of a nut 14engaging the threaded upper end of the bolt. A pressure spring 15 isinserted be- 3,136,479 Patented June 9, 1964 en e. yok a the pper Wallof a disc a chamri ch n els 1 p st e valve 18 n th r i ed t te may.

fu th r pa n o the. ischa ge. hamber. 6. v pe ings 21 in the yoke. 8.

Th va ve. seat member 4 s ormed w th a c r la y cylindrical internalsurface for cooperating with a valve body. The seat member is shown asformed with periphera y pa ed x l rows. f pe res 22 s in ed in FIG. 4.The valve body for cooperation with the internal surface of seat 4comprises an 'annularly bent strip 25 having ax a y, xt ng t gues ttherein wit spaces 27 therebetween. Said tongues are normally located inregister with the rows of apertures 22 so as to ye them and may. bartated to unco e he. per ur 9 a al ow. Pass ge working med m reth ou h bybending inwardly, during thesuction stroke when the,

piston is moving downwards and the pressure decreases.

The inward or uncoveringbending movement of the,

tenan s s. im ted y s p rmetl' y an annular p jection 29 of an uppermostcylinder wall member 5.

. In order to effect a capacity regulation the apertures 22 may becompletely uncovered by bringing the tongues 26 out of register with therows of apertures 22. To this end the valve body 25 is rotatably mountedwith relation to the valve seat member 4. For effecting a rotation ofthe valve body within predetermined limits is shown a snap by means ofwhich such a rotation may be rapidly carried out during the suctionstroke of the piston, since during this stroke the rotation isfacilitated due to the tongues not being forced against the valve seat.

The turning mechanism comprises two concentric rings 36 and 37 situatedon opposite sides of the lowermost portion of the seat member 4, saidportion which is designated by the reference numeral 40 in FIGS. 1a and1b being of a small radial width with relation to the radial width ofthe remaining portion of the seat member. Said rings 36 and 37 areconnected together by means of a substantially radial pin 41 passingfreely through a circumferentially elongate opening 42 formed in theseat portion 40.

Thus, by turning the ring 36 which is accessible from outside the innerring 37 as well as the valve body 25 connected thereto may be rotatedfrom the position shown in FIG. 2 into the position shown in FIG. 3 andback again. In order to prevent the valve seat member 4 from partakingin this rotation it is locked to the cylinder wall 1 by means of asubstantially axial pin 43, FIG. 1b.

The valve body 25 and the inner control ring 37 therefor are split likepiston rings in order to permit expansion due to increase oftemperature.

The rapid rotary movement of rings 36 and 37 hereinbefore referred tomay be effected by means of a ring 44 rotatably surrounding the ring 36while bearing also against the lower surface thereof, as shown in FIGS.1a and 1b. Said ring 44 may be rotated by movement in the directions ofthe arrows of an arm 45 connected, for instance, to a hydrauliccontrolling device, not shown. Inserted between the rings 36 and 44 atcircumferentially spaced points thereof are spirally wound springs 46the ends of which engage holes formed in the ring 36 and the ring 44,respectively.

To elfect setting of the valve body 25 into the inoperative positionindicated in FIG. 3 the arm 45 is subjected to a power acting in thedirection of the full arrow shown in FIG. 4; The resulting rotarymovement of ring 44 puts the springs 46 under tension and, afterreaching the position shown in FIG. 5, the springs are released during.

the suction stroke of the piston operating in the cylinder and moves thering 36 rapidly in clockwise direction to the position shown in FIG. 6corresponding to the position of the valve body shown in FIG. 3 in whichthe rows of apertures 22 are in register with the spaces 27. To restorethe valve body to normal position with the tongues 26 in register withthe rows of apertures the arm 45 is moved in the direction of the dottedarrow in FIG. 4,

causing the ring 44 to again tension the springs 46 and allow them torestore the rings 36 and 37 with the valve body to normal position.

Other quickly operating shifting device than that above described may beused without departing from the idea or scope of the invention.

each other, an annular valve body arranged in said valve seat andextending with its inner wall substantially in extension of the innerwall of said cylinder, said valve body having a plurality of am'allyextending tongues spaced angularly at equal intervals as said openings,a ring extending around the outside of said one end of said cylinderapproximately opposite said valve body, said seat portion having anadditional opening therein, means extending through said additionalopening and engaging said ring and valve body to transmit movementbetween said ring and valve body, a set of springs operably engagingwith their ends between said cylinder and said ring, and means forimparting circumferential movement to said ring to move said valve bodyangularly and to impart radial bias to said set of springs to cause saidspring to quickly shift said ring and valve body to the operativeor'inoperative position respectively of said valve tongues.

References (Jited in the file of this patent UNITED STATES PATENTSGermany Feb. 1,

